1. Field of the Invention:
The present invention relates to a cleaning device for cleaning the surface of an electrostatic latent image bearing member for use in a copying machine, printer or the like.
2. Description of the Prior Arts:
Conventional copying machines, printers or the like comprising an electrophotographic copy process have adapted a construction wherein residual toner particles or paper fragments remaining on the surface of a photosensitive drum are scraped off from the drum by a blade after a toner image formed on the surface of the drum is transferred onto a sheet.
Although toner particles or fiber components included in paper fragments can be removed by the blade, filling materials such as talc, calcium carbonate or the like having a diameter smaller than that of toner particles and contained in a sheet slip through the portion between the leading end of the blade and the photosensitive drum while coated on the surface of the drum due to the pressing power of the blade, producing a filming phenomenon. When this filming becomes thick, the surface potential of the photosensitive drum cannot be reduced upon the exposure of an image, causing deterioration of the image quality such as white-outs, slenderized character, deficiency of lines or the like.
On the other hand, there has been proposed a cleaning device which is different from a blade type device and employs a web. This web cleaning device is adapted to continuously or stepwisely feed a web material from a roller into pressing contact with the surface of the drum while taking up the web material by another roller, said device disclosed, for example, in U.S. Pat. No. 3,067,720.
However, in the above-mentioned web cleaning device, increased pressing power of the roller for completely removing the filming phenomenon increases rotating load of the photosensitive drum, causing the problem that a great load is imposed on the driving mechanism of the photosensitive drum.